Benzilic acid hydrazides as amine oxidase inhibitors



BENZHLIC A'CID HYDRAZIDES AS INHIBITORS c, and Lloyd M.

C a, assignors to uebec, Canada, a ec The present invention relates to nov 'v el hydrazide derivaproducts of the hydrazides which lowing general form hyl, isopropyl, secpropyl radicals present invention may be represented by the fol- 1 stands for h methyl or eth ydrogen methyl or ethyl and R stands for cycloh comes saturated.

enzilhydrazide, to

In carrying o an inert solven tical efiective acetic acid o d by including r other agents of be same nature as a Patented Jan. 29, 1963 invention were injected intraperitoneally and activity Differences between aration of the products of the present invention:

Example I 5 gm. of benzilhydrazide, M.P. 168-169 C., was red with 45 ml. of acetone for 1 hour The bulk of l-isopropylidene benzilhydrazide was quantitative, M.P. 194-195 C.

product in ml. of alcohol was of sodium borohydride at room temperature for 18 hours. The excess reducing agent was then discharged with 10% acetic acid.

The l-isopropyl benzilhydrazide tained melted at 143-145 C., wt. 4.66 g. ne recrystallization from alcohol gave material of M.P. 145.5 146.5 C.

Example 11 To a warm solution of 12.1 g. of benzilhydrazide in 150 ml. of anhydrous ethanol was added 9.0 m1. of redistilled methyl ethyl ketone, and the solution was refluxed for 178-179" C. in 94% yield By reducing the preceding product hydride in ethanol as described in Example I there was yield of l-cyclohexyl benzilhydrazide, MP. 155-l61 C. A single recrystallization from ethanol raised the melting point to 168.5-169.5 C.

The hydrochloride salt of the l-cyclohexyl benzilhydrazide was prepared by treating 5 g. of the base in 40 ml. of alcohol with 1.5 ml. of concentrated hydrochloric acid. After standing at room temperature for 20 minutes, the alcohol was removed by vacuum distillation and ether added. The white solid hydrochloride salt was collected.

obtained a 93.8%

Example IV 10 g. of benzzi-lhydrazide, 8.7 ml. of diethylketone and v 100 ml. of anhydrous alcohol were refluxed for two hours, and the solution was evaporated in vacuo. The solid residue was macerated with 40 ml. of ethyl ether, collected, washed with ethyl ether and dried. There was obtained 11.56 g. of l-(a-a, dimethylisopropylidene) benzilhydrazide, M.P. 128-128.5 C. Recrystallization from ethyl ether afforded an analytical sample of Ml. 128.5129.5 C.

7.5 g. of 1-(u,a', dimethylisopropylidene) benzilhydrazide was d treated with 0.92 g. of sodium borohydride at room temperature. Following acidification with 10% acetic acid, the mixture was dissolved in ethyl ether, washed with water,

' dried over sodium due. Crystallization from "5 .P.'8588 C. Re-

the'melting sulfate, ethyl-ether hexane aft methylisopropyl) benzilhydrazide, M crystallization from the same solvent raised point to 90-92 The hydrochloride salt was prepared in 90% yield as described in Example 3, M1. 159-162 C.

30 1933-42, pages 1933,

Example V To a warm solution of 30 g. of benzilhydr-azide in 400 ml. of anhydrous. ethanol was added 28 ml. of acetaldehyde, and the solution refluxed for two hours. Following the work-up as described in Example 4, there was isolated 30.6 g. of l-ethylidene benz'lhydrazide, MP 167-168 C.

Reduction of l-ethylidene benzilhydrazide with sodium borohydride in ethanol as described in Example I afforded l-ethyl-benzilhydrazide in 89% yield, M1. 129-133"- C. Recrystallization from ethyl ether afiorded l-ethyl benzilhydrazide MP. MES-144 C.

We claim:

1. l-sec-butyl-Z-benzilhydrazide.

2. Cyclohexyl benzilhydrazide HCl.

3. a,a'-Dimethylisopropyl benzilhydrazide HCl.

4. Ethyl beuzilhydrazide.

References Cited in the file of this patent UNITED STATES PATENTS 2,928,875 Martin et al Mar. 15, 1960 OTHER REFERENCES Beilsteins Handbuch der Organischen Chemie, vol. 10, First Supplement, page 153 (1932).

Offe et al.'. Z. Naturforsch, vol. 7-b, page 446-462, pages 446-454" relied on (1952) (C/559S) Yale et 211.: Town. v Chem. Soc, vol. 75, pages 1935, 1940 and 1941 relied on (1953) (C/559S). 

1. 1-SEC-BUTYL-2-BENZILHYDRAZIDE.
 2. CYCLOHEXYL BENZILHYDRAZIDE HCL. 